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Lesson 8-1: Length in the Customary System Conversions for Length in the Customary System (Conversion Factors) 1, 760 yd = 1 mi Strategy • When converting from a large unit to a small unit, multiply by the conversion factor. • When converting from a small unit to a larger unit, divide by the conversion factor. Units from: Small Inch (in) Foot (ft) Yard (yd) Large Mile (mi) Changing Units • Determine the direction of the change (LS or SL) • Determine if you are going to multiply or divide. Example 1 7 yards = _____ ft L S so you are going to multiply (1 yard = 3 feet) 7 X 3 = 21 Therefore 7 yd = 21 ft Example 2 2 miles = ______ ft LS 2 steps are needed. Step 1: Convert miles to yards Step 2: Convert yards to miles (1 mile = 1,760 yards) 2 miles = 3,520 yards (1 yard = 3ft) 3,520 yard = 10, 560 ft Therefore, 2 miles = 10,560 Ft Example 3 40 in = ______ ft SL 40 ÷ 12 1 1 We can divide fractions so that remainders can be described as fractions. 10 40 x 1 1 12 3 10 3 = 3 1 3 Therefore 40 in = 3 1/3 ft